59. Indigofera wightii Graham ex Wight & Arnott, Prodr. Fl. Ind. Orient. 202. 1834.
海南木蓝 hai nan mu lan
Indigofera hainanensis H. T. Tsai & T. T. Yu; I. inamoena Thwaites; I. pallida Craib.
Shrublets, 1-1.5 m tall. Stems with appressed white and brown medifixed symmetrically 2-branched trichomes. Stipules 1.5-2.5 mm, caducous. Leaves 3.5-5 cm, 11-19(-29)-foliolate; petiole and rachis adaxially grooved, with appressed gray medifixed trichomes; petiole ca. 1 cm; stipels minute; petiolules ca. 1 mm; leaflet blades opposite, elliptic-oblong to oblong-lanceolate, 5-10(-15) × 2.5-5(-8) mm, both surfaces with appressed white medifixed trichomes, midvein adaxially impressed and abaxially prominent ending in a tubular gland, secondary veins not visible, base cuneate, apex rounded to acute and mucronate. Racemes 1.5-3.5(-6) cm; peduncle 3-5 mm, with appressed gray medifixed trichomes; bracts triangular, ca. 1.5 mm, caducous. Pedicel 1-2 mm, with spreading trichomes, spreading or reflexed in fruit. Calyx 1.5-2 mm, with appressed medifixed trichomes; tube ca. 1 mm; teeth ovate, 1-1.2 mm. Corolla red; standard broadly ovate, ca. 6 mm, outside with dense 2-branched trichomes, base broadly cuneate, apex acute; wings narrowly elliptic, ca. 3 × 1 mm; keel ca. 6 × 1.5 mm. Stamens 5-5.5 mm; anthers ellipsoid, glabrous. Ovary hairy. Legume cylindric, 1.5-3 cm × 2-3 mm, with dense appressed medifixed trichomes; endocarp purplish red blotched. Seeds 6-11 per legume. Fl. Aug, fr. Oct-Nov. 2n = 16.
Sandy places on slopes or trailsides; 600-1800 m. Hainan [Cambodia, India, Laos, Myanmar, Sri Lanka, Thailand, Vietnam].